Streptocarpus, the Cape Primrose, will be the subject of the Saturday meeting of the Capital Area Chapter, American Gloxinia and Gesneriad Society. The speaker, Laura Progebin, chairman of the AGGS education committee, has written extensively for plant society publications. Her lecture will be illustrated with slides. The meeting, at noon at the U.S. National Arboretum, is open to the public free of charge. Jacqueline Mills, Arlington:
My hibiscus plant, bought several years ago and kept on an enclosed porch, hasn't bloomed since I purchased it when it had blossoms on it. Could it be that it needs more sun? Could I plant it outdoors or is the winter too cold for it in this area? Also, it is tall and leggy. Could I cut it back to make it fuller?
A: If your hibiscus is the Chinese, or tropical, Hibiscus, it is not hardy outdoors here. Many of the southern types are hardy in this area but are not generally grown as houseplants.
The Chinese hibiscus can be set outdoors in the summer. Give it an eastern exposure where it will get good sunlight about half the day and will not get too hot.
It is preferable not to plant your hibiscus in the garden in the summer; it is better to keep the roots confined in the pot they are to occupy the rest of the year.
Your plant may not be getting enough light to bloom. Also, the hibiscus has a dormant period. If it is dormant in the winter, it will bloom in the summer.
Another consideration is that your plant may need repotting with fresh soil in a larger pot.
The Chinese hibiscus can be pruned to force branching and to hold the dimensions of the plant to manageable size. The time to prune is in the spring. Cut out weak of spindly branches. Shorten main branches by about one-third. Cut with sharp, clean clippers about half an inch above an outward facing bud.
If you do a severe pruning job, remove the plant from the pot and prune some of the roots as well. Then repot in fresh soil, water the plant, and keep it in reduced light for a few days.
Cuttings from pruning can be rooted to make new plants; root cuttings in water, moist sand, or vermiculite.